1. Field of the Invention
The present invention relates to optical scopes including telescopes and binoculars, and more particularly to an anti-vibration telescope which allows stable observation by compensating for the influence of vibration due to, for example, shaking of the hand of the operator.
2. Description of Related Art
Various anti-vibration techniques have been proposed for cameras in order to eliminate the adverse affect of the shaking of the operator's hand while photographing. Also, in the field of surveying instruments, many types of inclination-correcting mechanisms have been developed in order to keep the horizontal line in the center of the reticle no matter how the main body of the surveying apparatus is inclined.
In general, if the optical axis of the object lens used in an optical apparatus shifts or tilts, the image is offset from the original focusing position. The basic idea of the anti-vibration or inclination correcting techniques mentioned above is to control the focus using some optically compensating means so as to bring the offset image back to the correct focal position.
However, if these conventional techniques are applied to telescopes or binoculars, vibration or fluctuation of the image can not be satisfactorily eliminated because the final image planes for the telescopes or binoculars are the retinas of the observer's eyes, and because eyepieces exist between the objective lenses and the eyes. Even if the image is kept stationary without vibration in the image plane of the objective lens under a conventional manner of control, the image formed on the retina can not be kept still because of the existence of the eyepiece which is likely to cause additional fluctuation.
Thus, the conventional anti-vibration technique is insufficient to compensate for image fluctuation or vibration in optical scopes which comprise an objective lens and an eyepiece.
It is, therefore, an object of the present invention to overcome these problems and provide an anti-vibration telescope that can keep the image formed on the retina substantially still even if the telescope is tilted.